/**
* Returns a copy of this date-time with the specified amount subtracted.
* <p>
* This returns a {@code ZonedDateTime}, based on this one, with the specified amount subtracted.
* The amount is typically {@link Period} or {@link Duration} but may be
* any other type implementing the {@link TemporalAmount} interface.
* <p>
* The calculation is delegated to the amount object by calling
* {@link TemporalAmount#subtractFrom(Temporal)}. The amount implementation is free
* to implement the subtraction in any way it wishes, however it typically
* calls back to {@link #minus(long, TemporalUnit)}. Consult the documentation
* of the amount implementation to determine if it can be successfully subtracted.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param TemporalAmount $amountToSubtract the amount to subtract, not null
* @return ZonedDateTime a {@code ZonedDateTime} based on this date-time with the subtraction made, not null
* @throws DateTimeException if the subtraction cannot be made
* @throws ArithmeticException if numeric overflow occurs
*/
public function minusAmount(TemporalAmount $amountToSubtract)
{
if ($amountToSubtract instanceof Period) {
$periodToSubtract = $amountToSubtract;
return $this->resolveLocal($this->dateTime->minusAmount($periodToSubtract));
}
return $amountToSubtract->subtractFrom($this);
}
